2.2 Data source
JMDC data includes patient-level demographic information, inpatient and
outpatient data—such as diagnosis and procedures—and prescriptions.
Claims data are collected from clinics, hospitals and pharmacies; these
records are traceable even when an enrollee utilizes different
healthcare providers. Prescriptions, procedures, admissions, and the
beginning of medical care are indexed by date. All diagnoses are coded
using International Classification of the Diseases, Tenth
Revision (ICD-10) code, along with Japanese standardized diagnostic
codes. The latter provide more detailed information than ICD-10 code,
such as influenza virus type (eg, type A, type B or unspecified). All
prescriptions refer Anatomical Therapeutic Chemical Classification
System code together with brand name, and procedures are encoded using
Japanese-specific procedure codes.